It's also not simply offending language that equals defamation.
From wikipedia:
"Opinion is a defence recognized in nearly every jurisdiction. If the allegedly defamatory assertion is an expression of opinion rather than a statement of fact, defamation claims usually cannot be brought because opinions are inherently not falsifiable."
also
"In Common Law it is usually a requirement that this claim be false."
Based on the post, many of the tweets were insult - direct attacks against the author, and not simply criticism/opinions.
All but 4 states in the US also recognize cases of defamation per se, where the truth of the claims is irrelevant, and the damages are predetermined. Claims which impute the following fall under that category (I've omitted 2 of the 4):
1. Allegations or imputations "injurious to another in their trade, business, or profession"
2. Allegations or imputations "of loathsome disease" (historically leprosy and sexually transmitted disease, now also including mental illness)
Many of the tweets directed at him fall into that category, and hence are defamation per se.I think mostly we're discussing something else here, angry and vitriolic "piling-on" responses, which is a different issue from defaming someone.
The government censors people through force, sometimes in autocracies this quite literally means a gun to a dissenter's head.
It is a separate thing all together, On the other hand, if individuals freely choose to criticize, flame, or just simple disassociate themselves with someone else because they disapprove of their opinions. We should all be free to do at least this without fear that merely by agreeing with the majority we will be accused of 'censoring' the minority.